JPH0310399B2 - - Google Patents
Info
- Publication number
- JPH0310399B2 JPH0310399B2 JP63325983A JP32598388A JPH0310399B2 JP H0310399 B2 JPH0310399 B2 JP H0310399B2 JP 63325983 A JP63325983 A JP 63325983A JP 32598388 A JP32598388 A JP 32598388A JP H0310399 B2 JPH0310399 B2 JP H0310399B2
- Authority
- JP
- Japan
- Prior art keywords
- activated carbon
- membrane
- powdered activated
- treatment
- denitrification
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 72
- 238000000034 method Methods 0.000 claims description 60
- 230000008569 process Effects 0.000 claims description 49
- 239000012528 membrane Substances 0.000 claims description 40
- 239000010802 sludge Substances 0.000 claims description 30
- 238000000926 separation method Methods 0.000 claims description 21
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 21
- 239000002002 slurry Substances 0.000 claims description 14
- 239000002351 wastewater Substances 0.000 claims description 11
- 238000000108 ultra-filtration Methods 0.000 claims description 6
- 230000002378 acidificating effect Effects 0.000 claims description 5
- 238000001471 micro-filtration Methods 0.000 claims description 3
- 239000002518 antifoaming agent Substances 0.000 description 12
- 238000001179 sorption measurement Methods 0.000 description 11
- 239000010800 human waste Substances 0.000 description 9
- 238000005189 flocculation Methods 0.000 description 8
- 230000016615 flocculation Effects 0.000 description 8
- 238000005187 foaming Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 7
- 230000004907 flux Effects 0.000 description 6
- 230000008929 regeneration Effects 0.000 description 6
- 238000011069 regeneration method Methods 0.000 description 6
- 238000002156 mixing Methods 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 238000012423 maintenance Methods 0.000 description 4
- 229910052698 phosphorus Inorganic materials 0.000 description 4
- 239000011574 phosphorus Substances 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000001556 precipitation Methods 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 239000006260 foam Substances 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 229920001296 polysiloxane Polymers 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000003254 anti-foaming effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000149 chemical water pollutant Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000013530 defoamer Substances 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000000909 electrodialysis Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- -1 human waste Chemical compound 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000009916 joint effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000009285 membrane fouling Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000001546 nitrifying effect Effects 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 239000003002 pH adjusting agent Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000001223 reverse osmosis Methods 0.000 description 1
- UKLNMMHNWFDKNT-UHFFFAOYSA-M sodium chlorite Chemical compound [Na+].[O-]Cl=O UKLNMMHNWFDKNT-UHFFFAOYSA-M 0.000 description 1
- 229960002218 sodium chlorite Drugs 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
Landscapes
- Removal Of Specific Substances (AREA)
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Activated Sludge Processes (AREA)
- Water Treatment By Sorption (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Description
〔産業上の利用分野〕
本発明は、し尿、浄化槽汚泥、ごみ埋立て滲出
汚水などの窒素分を含む有機性汚水を生物学硝化
脱窒素処理を含む処理工程で処理するさいに、生
物学硝化脱窒素処理工程での発泡現象が生じない
ようにするなどとともに高度に浄化された処理水
を安定して得る有機性汚水の処理方法に関する。
特に、本発明は、本出願人が先に出願した特願昭
62−266214（特開昭63−214397）「高濃度有機性廃
水の処理方法」の発明を改良したものである。
〔従来技術〕
し尿などの窒素、リンを多量に含む有機性汚水
を処理するための従来の最も代表的な処理方法
は、第２図に示すフローシートからなるプロセス
を有するもので、実際に多く用いられている。こ
のプロセスは「高負荷脱窒素プロセス」と呼ばれ
ている。
しかしながら、このプロセスは、硝化脱窒素処
理工程での発泡が激しいので、多量の消泡剤を添
加しないと、同処理工程において活性汚泥の付着
した泡が槽外に溢れ出し、硝化脱窒素処理が全く
不可能となるという重大な欠点があつた。また、
ここで使用される消泡剤は一般にシリコーン系あ
るいはアルコール系のものが使用されていて、こ
のものは高濃度のCOD含有物質でもあるので、
その消泡剤の添加によつて処理水のCODが悪化
しやすいという問題もあつた。さらに、このプロ
セスでは、活性汚泥スラリーの固液分離が一般に
沈殿法によつているため、固液分離工程でのSS
のキヤリオーバーが起きやすく、また活性炭吸着
塔、活性炭再生炉が不可欠であるため、メンテナ
ンスが煩雑で、装置費も高いという問題点もあつ
た。
これに対応して、この高負荷脱窒素プロセスに
おける沈殿工程の代りに、限外濾過膜（UF膜）
又は精密濾過膜（MF膜）による膜分離を用いる
ことによりSSのキヤリオーバーを完全に防止す
るという新技術が最近開発され、数ケ所の実施設
で採用されるようになつた。
この膜分離方式を利用した有機性汚水の処理方
法は「UF膜分離リン吸着プロセス」と呼ばれ、
その工程は第３図のフローシートに示す通りであ
る。
この方式は、沈殿工程が完全に不要なので、固
液分離工程の維持管理性が従来より大幅に向上す
るという特長をもつているが、やはり、無希釈硝
化脱窒素処理工程において多量の消泡剤を必要と
し、活性炭吸着塔と活性炭再生炉を必要とするこ
とは、第２図の高負荷脱窒素プロセスと同様であ
り、これらの面ではなんら改善されていない。し
かも、このUF膜分離リン吸着プロセスはPO4 3-
吸着除去工程を必要とするので、その吸着剤の再
生操作が煩雑であり、再生廃液の処分問題にも直
面するという大きな欠点があつた。
次に、本出願人が先に出願した特願昭62−
266214（特開昭63−214397）「高濃度有機性廃水の
処理方法」は、第４図のフローシートに示すよう
に、凝集処理と膜分離とを結合したものであつ
て、UF膜分離リン吸着プロセスにおけるPO4 3-
吸着除去工程が不要であるという長所をもつてい
るが、前記両プロセスと同様に消泡剤、活性炭吸
着塔、活性炭再生炉の三者を必要とするという欠
点をもつており、理想的なプロセスとはいえなか
つた。
〔発明が解決しようとする課題〕
本発明は、以上のような従来技術の欠点を根本
的に解決することを課題とするもので、具体的に
は次の点の発明の解決課題とするものである。
(1) 生物学的硝化脱窒素処理工程への消泡剤の添
加を不要あるいは大巾に削減出来る無発泡プロ
セスを確立すること。これにより、処理コスト
を高くしていた消泡剤費用をゼロあるいは僅小
にすること。
(2) 活性炭吸着塔、活性炭再生炉を不要にするこ
と。これにより、建設費を大幅に削減し、プロ
セスを簡潔化し、維持管理性を高めること。
〔課題を解決するための手段〕
本発明は、有機性汚水を生物学的硝化脱窒素処
理をした後、該処理工程からの活性汚泥スラリー
に無機凝集剤、粉末活性炭を添加混合し、PHを酸
性条件下に維持しつつ限外濾過膜又は精密濾過膜
により膜分離し、清澄処理水を得る一方、該膜分
離工程で分離された粉末活性炭共存凝集汚泥の少
なくとも一部を前記生物学的硝化脱窒素処理工程
に供給することを特徴とする有機性汚水の処理方
法である。
以下、本発明を実施する装置の模式図を示した
第１図を参照しながら、し尿処理を例に挙げて、
本発明を詳しく説明する。
除渣し尿１は、無希釈型の生物学的硝化脱窒素
処理工程２に流入し、そこで硝化脱窒素され、同
時にBODも除去される。同処理工程としては、
硝化液循環型、ステツプ流入型、一槽型、好気的
脱窒素型などの公知の任意の方式を適用して差し
支えない。
前記の生物学的硝化脱窒素処理工程２から流出
する活性汚泥スラリー３に、塩化第２鉄、ポリ硫
酸第２鉄などの鉄 凝集剤４、もしくは硫酸ばん
土、ポリ塩化アルミニウムなどのアルミニウム系
凝集剤４′を添加し、PHを弱酸性条件に維持して
混和槽５で撹拌し、凝集フロツク形成を行うこと
によつて、活性汚泥スラリー３中に高濃度に含ま
れる非生物分解性COD、色度成分及びPO4 3-イオ
ンを凝集不溶化する。そのさいのPHは4.0〜5.5が
好適で、COD、色度、PO4 3-の除去率が向上する
とともに後記のUF膜の透過流束も増加する。な
お、混和槽５は省略し、管路撹拌でもかまわな
い。
しかして、凝集処理を受けた活性汚泥スラリー
６に粉末活性炭７を添加し、接触槽８にて所定時
間滞留させ、凝集処理によつてもなお水中に残留
するCOD、色度を活性炭に吸着する。図示の接
触槽８は空気撹拌を行うものである。９は空気で
ある。接触槽８内における滞留時間は、通常30〜
90分で良い。
次に、粉末活性炭が共存する凝集スラリー１０
を限外濾過膜又は精密濾過膜を用いる膜分離装置
１１にポンプ圧送し、膜分離し、SSゼロの無色
透明な膜透過水（高度処理水）１２を得る。膜分
離装置１１は、チユーブラー型、平膜型のクロス
フロータイプのものを用いるのが好ましい。
膜透過水１２は無菌であり、COD、色度、窒
素成分、PO4 3-、SSが極めて高度に除去されてい
るので、そのまま公共用水域に放流あるいは再利
用することができる。なお、再利用する場合に
は、膜透過水を逆浸透又は電気透析によつてあら
かじめ脱塩することが好ましい。
一方、膜分離工程で分離された粉末活性炭共存
凝集汚泥１３の一部１４は混和槽５に循環され、
残部１５は生物学的硝化脱窒素処理工程２に供給
される。
なお、１６は余剰汚泥であり、汚泥脱水工程へ
供給される。余剰汚泥は粉末活性炭共存凝集汚泥
１３から抜き出してもよいが、第１図示例のよう
にするのが好ましい。また１７は、凝集処理を弱
酸性（PH4.0〜5.5）に調整するためのPH調整剤で
ある。
活性汚泥スラリーに対する無機凝集剤の添加量
は、通常1500〜3000mg／の範囲とし、また粉末
活性炭の添加量は通常100〜800mg／、好ましく
は150〜500mg／の範囲とするのがよい。本発明
で使用する粉末活性炭は、市販されているものを
そのまま使用することができ、その粒度は平均粒
径が100メツシユ以下のものが好ましい。なお、
無機凝集剤と粉末活性炭の添加は、実施例のよう
に無機凝集剤を先にするのが好ましいが、無機凝
集剤が十分混合されない中に粉末活性炭を添加し
ても同じ効果が得られることから、同時でもかま
わない。
また、前記粉末活性炭共存凝集汚泥１３から生
物学的硝化脱窒素処理工程２へ送る部分１５の量
については、この硝化脱窒素処理工程への返送量
をV1、凝集処理工程への返送量をV2とするとき、
V1は硝化脱窒素処理工程２のMLSSを所定濃度
に維持するのに必要な量に設定され、ほぼ一定で
あるのに対し、V2は任意の量に設定される。従
つて、（V2／V1）の値は0.5〜数100と広範囲の値
をとりうる。通常は200程度に設定される。
〔作用〕
本発明においては、生物学的硝化脱窒素処理工
程２に凝集処理後の残留COD成分などを吸着し
た粉末活性炭を含んだ凝集汚泥１５を供給する
と、驚くべきことに、同処理工程での発泡が著し
く抑止あるいは全くなくなり、消泡剤の添加が僅
小、もしくは不必要になり、消泡機が完全に不要
になることが見出された。このような作用が生じ
る機構については、粉末活性炭と凝集汚泥とのど
のような共同作用によるものかはつきりしない
が、いずれにしてもその添加により上記の作用が
顕著に生じる。すなわち、し尿の無希釈生物学的
処理プロセスの最大の懸案が解決することが見出
された。
さらに、粉末活性炭共存凝集汚泥１４を混和槽
５での凝集処理に循環すると、塩化第２鉄などの
無機凝集剤の所要薬注率が20％ほど節減できるこ
とが認められた。このことは重要な意味をもつて
おり、汚泥発生量が減少し、汚泥処理が合理化で
きるという大きな効果が出る。
もう一つの重要な作用としては、粉末活性炭が
共存する凝集スラリーを膜分離する場合、粉末活
性炭無共存時に比べ、膜透過流束（フラツクス）
（m3／m2・膜・日）が向上することも発見された。
本発明においては、粉末活性炭などを前記した
個所で活性汚泥スラリーに添加し、かつそれによ
り生じた粉末活性炭共存凝集汚泥の少なくとも一
部を硝化脱窒素処理工程に供給することにより上
記の作用を生じるのであつて、粉末活性炭が発泡
防止に役立つているのではないかとの観点から、
もしも新鮮な粉末活性炭を、たとえば生物学的硝
化脱窒素処理工程に添加すると、該処理工程の液
の高濃度の溶解性CODと色度成分（凝集処理後
のCOD、色度の約10倍もの高濃度を示す）と粉
末活性炭が接触することになること、およびこれ
らのCOD、色度成分が活性炭によつて吸着され
難い高分子量成分であることにより、放流水の
COD、色度が本発明における放流水よりも４〜
５倍も高い値になり、トータルプロセスとして評
価した場合に極めて不合理な結果を招く。したが
つて、新鮮な粉末活性炭を生物学的硝化脱窒素処
理工程に添加する方法では、総合的な水質向上度
が本発明に比べ極めて劣るという結果をもたら
す。
〔実施例〕
以下、実施例によつて本発明を具体的に説明す
る。ただし、本発明はこの実施例のみに限定され
るものではない。
実施例
第１図の模式図に示す、本発明を実施するため
の装置によつて、し尿を処理した。
第１表に示す水質の除渣し尿を、後記する粉末
活性炭共存凝集汚泥を循環しつつ一槽型の無希釈
タイプ硝化脱窒素処理を行つた。その処理におけ
る運転条件は第２表に示すとおりである。
[Industrial Application Field] The present invention is applicable to biological nitrification when treating nitrogen-containing organic wastewater such as human waste, septic tank sludge, and landfill leachate in a treatment process that includes biological nitrification and denitrification treatment. The present invention relates to a method for treating organic wastewater that prevents foaming during the denitrification process and stably produces highly purified treated water.
In particular, the present invention is based on the patent application filed earlier by the applicant.
62-266214 (Japanese Unexamined Patent Publication No. 63-214397) ``Method for treating highly concentrated organic wastewater'' is improved. [Prior Art] The most typical conventional treatment method for treating organic wastewater containing large amounts of nitrogen and phosphorus, such as human waste, has a process consisting of a flow sheet as shown in Figure 2. It is used. This process is called a "high-load denitrification process." However, in this process, foaming is intense during the nitrification and denitrification treatment process, so if a large amount of antifoaming agent is not added, activated sludge-adhered foam will overflow outside the tank during the nitrification and denitrification treatment process, and the nitrification and denitrification process will be interrupted. There was a major drawback in that it was completely impossible. Also,
The antifoaming agents used here are generally silicone-based or alcohol-based, and these also contain high concentrations of COD.
There was also the problem that the addition of the antifoaming agent tended to worsen the COD of the treated water. Furthermore, in this process, the solid-liquid separation of activated sludge slurry is generally performed by the precipitation method, so SS in the solid-liquid separation process is
There were also problems in that carry-over was likely to occur, and that an activated carbon adsorption tower and activated carbon regeneration furnace were essential, making maintenance complicated and equipment costs high. Correspondingly, ultrafiltration membranes (UF membranes) are used instead of the precipitation step in this high-load denitrification process.
A new technology has recently been developed that completely prevents SS carryover by using membrane separation using microfiltration membranes (MF membranes), and has been adopted in several actual facilities. The method of treating organic wastewater using this membrane separation method is called "UF membrane separation phosphorus adsorption process".
The process is as shown in the flow sheet of FIG. This method has the advantage that the maintenance process of the solid-liquid separation process is significantly improved compared to the conventional method because the precipitation process is completely unnecessary. The need for an activated carbon adsorption tower and an activated carbon regeneration furnace is similar to the high-load denitrification process shown in FIG. 2, and there is no improvement in these aspects. Moreover, this UF membrane separation phosphorus adsorption process reduces PO 4 3-
Since an adsorption removal step is required, the regeneration operation of the adsorbent is complicated, and there are major drawbacks such as the problem of disposal of the regenerated waste liquid. Next, the patent application filed earlier by the applicant in 1982-
266214 (Japanese Unexamined Patent Publication No. 63-214397) ``Method for treating highly concentrated organic wastewater'' is a combination of flocculation treatment and membrane separation, as shown in the flow sheet of Figure 4. PO 4 3- in adsorption process
Although it has the advantage of not requiring an adsorption removal process, it has the disadvantage of requiring three components: an antifoaming agent, an activated carbon adsorption tower, and an activated carbon regeneration furnace, similar to both of the above processes, making it an ideal process. However, I could not say that. [Problems to be Solved by the Invention] The present invention aims to fundamentally solve the drawbacks of the prior art as described above, and specifically, the following problems are to be solved by the invention. It is. (1) Establish a non-foaming process that can eliminate or greatly reduce the addition of antifoaming agents to the biological nitrification and denitrification treatment process. This makes it possible to eliminate or minimize the cost of antifoaming agent, which increases the processing cost. (2) Eliminate the need for activated carbon adsorption towers and activated carbon regeneration furnaces. This will significantly reduce construction costs, simplify processes, and improve maintenance. [Means for Solving the Problems] The present invention performs biological nitrification and denitrification treatment on organic wastewater, and then adds and mixes an inorganic flocculant and powdered activated carbon to the activated sludge slurry from the treatment process to reduce the pH. Membrane separation is performed using an ultrafiltration membrane or a microfiltration membrane while maintaining under acidic conditions to obtain clarified treated water, while at least a portion of the powdered activated carbon-coexisting flocculated sludge separated in the membrane separation step is subjected to the biological nitrification. This is a method for treating organic wastewater characterized by supplying it to a denitrification treatment process. Hereinafter, with reference to FIG. 1 showing a schematic diagram of an apparatus implementing the present invention, human waste treatment will be taken as an example.
The present invention will be explained in detail. The removed human waste 1 flows into a undiluted biological nitrification and denitrification treatment step 2, where it is nitrified and denitrified and BOD is also removed at the same time. The processing process is as follows:
Any known method such as a nitrifying solution circulation type, a step inflow type, a single tank type, or an aerobic denitrification type may be applied. The activated sludge slurry 3 flowing out from the biological nitrification and denitrification treatment process 2 is treated with an iron flocculant 4 such as ferric chloride or polyferric sulfate, or an aluminum flocculant such as sulfate clay or polyaluminum chloride. The non-biodegradable COD contained in the activated sludge slurry 3 at a high concentration is removed by adding the agent 4' and stirring it in the mixing tank 5 while maintaining the pH at a slightly acidic condition to form agglomerated flocs. Chromaticity components and PO 4 3- ions are aggregated and insolubilized. The pH at this time is preferably 4.0 to 5.5, and the removal rate of COD, chromaticity, and PO 4 3- is improved, and the permeation flux of the UF membrane described later is also increased. Note that the mixing tank 5 may be omitted and pipe stirring may be used. Powdered activated carbon 7 is then added to the activated sludge slurry 6 that has undergone flocculation treatment, and is allowed to remain in the contact tank 8 for a predetermined period of time, allowing the activated carbon to adsorb COD and chromaticity that remain in the water even after the flocculation treatment. . The illustrated contact tank 8 performs air agitation. 9 is air. The residence time in the contact tank 8 is usually 30~
90 minutes is fine. Next, agglomerated slurry 10 in which powdered activated carbon coexists
The water is pumped to a membrane separation device 11 using an ultrafiltration membrane or a precision filtration membrane and subjected to membrane separation to obtain colorless and transparent membrane permeated water (highly treated water) 12 with zero SS. The membrane separation device 11 is preferably of a cross-flow type, such as a tubular type or a flat membrane type. The membrane-permeated water 12 is sterile and has COD, chromaticity, nitrogen components, PO 4 3- and SS removed to an extremely high degree, so it can be discharged into public water bodies or reused as is. In addition, when reusing, it is preferable to desalinate the membrane-permeated water in advance by reverse osmosis or electrodialysis. On the other hand, a part 14 of the powdered activated carbon coagulated sludge 13 separated in the membrane separation process is circulated to the mixing tank 5,
The remaining portion 15 is supplied to the biological nitrification and denitrification treatment step 2. Note that 16 is surplus sludge, which is supplied to the sludge dewatering process. Although the excess sludge may be extracted from the powdered activated carbon-coexisting flocculated sludge 13, it is preferable to do so as in the first illustrated example. Further, 17 is a pH adjusting agent for adjusting the aggregation treatment to be weakly acidic (PH4.0 to 5.5). The amount of inorganic flocculant added to the activated sludge slurry is usually in the range of 1500 to 3000 mg/, and the amount of powdered activated carbon added is usually in the range of 100 to 800 mg/, preferably 150 to 500 mg/. The powdered activated carbon used in the present invention can be used as is on the market, and preferably has an average particle size of 100 mesh or less. In addition,
When adding the inorganic flocculant and powdered activated carbon, it is preferable to add the inorganic flocculant first as in the example, but the same effect can be obtained even if the powdered activated carbon is added before the inorganic flocculant is sufficiently mixed. , even at the same time. Furthermore, regarding the amount of the portion 15 to be sent from the powdered activated carbon coexisting flocculated sludge 13 to the biological nitrification and denitrification treatment process 2, the amount returned to the nitrification and denitrification treatment process is V 1 , and the amount returned to the flocculation treatment process is V 1 . When V 2 ,
V 1 is set to an amount necessary to maintain the MLSS in the nitrification and denitrification treatment step 2 at a predetermined concentration and is approximately constant, whereas V 2 is set to an arbitrary amount. Therefore, the value of (V 2 /V 1 ) can take a wide range of values from 0.5 to several hundred. Usually it is set to around 200. [Function] In the present invention, when the flocculated sludge 15 containing powdered activated carbon that has adsorbed residual COD components after flocculation treatment is supplied to the biological nitrification and denitrification treatment step 2, surprisingly, in the same treatment step, It has been found that foaming is significantly suppressed or completely eliminated, the addition of antifoaming agents is minimal or unnecessary, and antifoaming machines are completely unnecessary. The mechanism by which such an action occurs is not clear as to what kind of joint action between the powdered activated carbon and the flocculated sludge is involved, but in any case, the above-mentioned action is significantly produced by its addition. In other words, it has been found that the greatest concern regarding the undiluted biological treatment process for human waste has been solved. Furthermore, it has been found that when the powdered activated carbon coexisting flocculated sludge 14 is circulated for flocculation treatment in the mixing tank 5, the required chemical injection rate of an inorganic flocculant such as ferric chloride can be reduced by about 20%. This has an important meaning, and has the great effect of reducing the amount of sludge generated and streamlining sludge treatment. Another important effect is that when membrane-separating an agglomerated slurry in which powdered activated carbon coexists, the membrane permeation flux (flux) decreases compared to when powdered activated carbon does not coexist.
It was also discovered that (m 3 /m 2・film・day) was improved. In the present invention, the above effects are produced by adding powdered activated carbon or the like to the activated sludge slurry at the above-described location, and supplying at least a portion of the resulting flocculated sludge coexisting with powdered activated carbon to the nitrification and denitrification treatment process. Therefore, from the perspective that powdered activated carbon may be useful in preventing foaming,
If fresh powdered activated carbon is added, for example, to a biological nitrification and denitrification treatment process, it will result in high concentrations of soluble COD and chromatic components (about 10 times the COD and chromaticity after flocculation treatment) in the process liquor. The effluent water is
COD, chromaticity is 4 to 4 higher than the effluent water in the present invention.
The value is five times higher, leading to extremely unreasonable results when evaluated as a total process. Therefore, the method of adding fresh powdered activated carbon to the biological nitrification and denitrification treatment process results in an overall water quality improvement that is extremely inferior to that of the present invention. [Example] Hereinafter, the present invention will be specifically explained with reference to Examples. However, the present invention is not limited to this example. Example Human waste was treated using an apparatus for carrying out the present invention as shown in the schematic diagram of FIG. A one-tank, non-dilution type nitrification and denitrification treatment was carried out on the filtered human waste having the water quality shown in Table 1 while circulating it through powdered activated carbon-coexisting flocculated sludge, which will be described later. The operating conditions for this treatment are as shown in Table 2.
【表】【table】
【表】
次に、生物学的硝化脱窒素処理工程２の活性汚
泥スラリー３にFeCl3を2000mg／（し尿１m3あ
たり2.6KgのFeCl3）添加し、PH4.0〜4.5の弱酸性
条件下で５分間撹拌した後、粉末活性炭をし尿１
m3あたり400ｇ添加し、60分空気撹拌した。
しかるのち、２の粉末活性炭が共存する凝集ス
ラリーをクロスフローによるチユーブラモジユー
ル限外濾過膜（UF膜）（公称分画分子量10万）に
よつて膜分離した結果、第３表に示す水質の膜透
過水、すなわち高度処理水を得た。[Table] Next, 2000 mg of FeCl 3 / (2.6 kg of FeCl 3 per 1 m 3 of human waste) was added to the activated sludge slurry 3 of biological nitrification and denitrification treatment step 2, and the mixture was added under slightly acidic conditions of PH 4.0 to 4.5. After stirring for 5 minutes with
400 g per m 3 was added and air stirred for 60 minutes. Afterwards, the agglomerated slurry in which powdered activated carbon coexists in Step 2 was separated by a cross-flow tubular module ultrafiltration membrane (UF membrane) (nominal molecular weight cut off: 100,000), resulting in the water quality shown in Table 3. The membrane-permeated water, that is, highly treated water, was obtained.
【表】【table】
【表】
前記運転条件下による運転結果によれば、８ケ
月間にわたる試験期間中、生物学的硝化脱窒素処
理工程に消泡剤を添加しなくても、発泡はほとん
ど認められず、円滑な処理が可能であつた。その
さい生物処理槽では泡はその槽の水面上10〜15cm
のところにとどまつていた。このため消泡機も不
要であつた。
また、その膜分離におけるUF膜の透過流束
（Flux）は2.0〜2.1m3／m2・日という高い値が安
定して得られた。膜汚染防止のための亜塩素酸ソ
ーダ（濃度100mg／）によるUF膜の所要洗浄頻
度は、５ケ月に１回とかなり少なくしてすんだ。
比較例
第１図に示す処理装置により行われる実施例の
処理方法において粉末活性炭を添加しない以外
は、同じ条件で処理を行つたところ、生物学的硝
化脱窒素処理工程での発泡が激しく、シリコーン
系消泡剤を常時150〜200mg／添加しないと、汚
泥が付着した泡が槽外に溢れだし、処理不能とな
つた。
また、上記の粉末活性炭を添加しない場合に、
生物学的硝化脱窒素処理工程に消泡剤を添加する
ようにして処理し、同処理工程から得られる活性
汚泥スラリーにFeCl3を2500mg／添加し、PH4.0
〜4.5の条件で凝集処理し、実施例と同じクロス
フローによるチユーブラモジユール限外濾過膜で
膜分離したところ、膜透過水質は第４表に示すよ
うに、COD、色度とＴ−Ｎが悪化し、またBOD
もやや悪化した。[Table] According to the operation results under the above operating conditions, during the 8-month test period, almost no foaming was observed and smooth treatment was achieved even without adding an antifoaming agent to the biological nitrification and denitrification treatment process. It was possible to treat it. At that time, in the biological treatment tank, the bubbles are 10 to 15 cm above the water surface of the tank.
He stayed there. Therefore, a defoamer was not necessary. Moreover, the permeation flux (Flux) of the UF membrane in the membrane separation was stably obtained at a high value of 2.0 to 2.1 m 3 /m 2 ·day. The frequency of cleaning of the UF membrane with sodium chlorite (concentration 100mg/) to prevent membrane contamination has been reduced to once every five months. Comparative Example When treatment was carried out under the same conditions as in the treatment method of the example carried out using the treatment equipment shown in Figure 1, except that powdered activated carbon was not added, foaming was severe in the biological nitrification and denitrification treatment process, and silicone If 150 to 200 mg of antifoaming agent was not added at all times, foam with sludge attached would overflow outside the tank, making it impossible to treat it. In addition, when the above powdered activated carbon is not added,
An antifoaming agent is added to the biological nitrification and denitrification treatment process, and 2500mg/FeCl 3 is added to the activated sludge slurry obtained from the same treatment process, resulting in a pH of 4.0.
When flocculation treatment was carried out under the conditions of ~4.5 and membrane separation was performed using a tubular module ultrafiltration membrane using the same cross flow as in the example, the membrane permeated water quality was determined by COD, chromaticity and T-N as shown in Table 4. becomes worse and BOD
It got a little worse.
【表】【table】
本発明は、次のような効果を有する。
(1) 生物学的硝化脱窒素処理工程での発泡を効果
的に抑止することが可能であり、従来の処理プ
ロセスで多量に必要としていた消泡剤が不要、
あるいは大巾に削減可能となり、ランニングコ
ストの低減、維持管理性の向上効果があるほ
か、COD発現物質である消泡剤が添加されな
いので、処理水のCODが低減する。また、生
物学的硝化脱窒素反応の効率が向上し、安定し
て処理が行える。
(2) 無機凝集剤の所要注入率が低減し、汚泥の発
生量も減少する。
(3) 活性炭吸着塔、活性炭再生炉が不要になり、
プロセスの構成が簡単になり、維持管理性、設
置面積、建設費のすべての面で非常に有利にな
る。
(4) 膜分離工程における膜の透過流束が向上し、
膜汚染進行度も減少する。
The present invention has the following effects. (1) It is possible to effectively suppress foaming during the biological nitrification and denitrification treatment process, eliminating the need for large amounts of antifoaming agents, which were required in conventional treatment processes.
Alternatively, it is possible to significantly reduce COD, which has the effect of reducing running costs and improving maintenance and manageability, and because no antifoaming agent, which is a COD-producing substance, is added, the COD of treated water is reduced. In addition, the efficiency of biological nitrification and denitrification reactions is improved, allowing stable processing. (2) The required injection rate of inorganic flocculant is reduced, and the amount of sludge generated is also reduced. (3) Activated carbon adsorption tower and activated carbon regeneration furnace are no longer required.
The process is easy to configure and has significant advantages in terms of maintainability, footprint, and construction costs. (4) Improved membrane permeation flux in the membrane separation process,
The progress of membrane fouling is also reduced.
第１図は、本発明を実施する装置の模式図を示
し、第２図は従来の「高負荷脱窒素プロセス」の
フローシートを示し、第３図は、従来の「UF膜
分離リン吸着プロセス」のフローシートを示し、
第４図は、本願人が先に出願した「高濃度有機性
廃水の処理方法」のフローシートを示す。
１……除渣し尿、２……生物学的硝化脱窒素処
理工程、３……活性汚泥スラリー、５……混和
槽、４……無機凝集剤、８……接触槽、７……粉
末活性炭、１５……粉末活性炭共存凝集汚泥の一
部、１１……膜分離装置。
Fig. 1 shows a schematic diagram of an apparatus for carrying out the present invention, Fig. 2 shows a flow sheet of a conventional "high-load denitrification process", and Fig. 3 shows a conventional "UF membrane separation phosphorus adsorption process". ” flow sheet,
FIG. 4 shows a flow sheet of the "method for treating highly concentrated organic wastewater" previously filed by the applicant. 1... Removal human waste, 2... Biological nitrification and denitrification treatment process, 3... Activated sludge slurry, 5... Mixing tank, 4... Inorganic flocculant, 8... Contact tank, 7... Powdered activated carbon , 15...Part of flocculated sludge coexisting with powdered activated carbon, 11... Membrane separation device.
Claims (1)
後、該処理工程からの活性汚泥スラリーに無機凝
集剤、粉末活性炭を添加混合し、PHを酸性条件下
に維持しつつ限外濾過膜又は精密濾過膜により膜
分離し、清澄処理水を得る一方、該膜分離工程で
分離された粉末活性炭共存凝集汚泥の少なくとも
一部を前記生物学的硝化脱窒素処理工程に供給す
ることを特徴とする有機性汚水の処理方法。1 After biological nitrification and denitrification treatment of organic wastewater, an inorganic flocculant and powdered activated carbon are added and mixed to the activated sludge slurry from the treatment process, and while maintaining the pH under acidic conditions, ultrafiltration membrane or The method is characterized in that, while membrane separation is performed using a microfiltration membrane to obtain clear treated water, at least a portion of the powdered activated carbon-coexisting flocculated sludge separated in the membrane separation step is supplied to the biological nitrification and denitrification treatment step. How to treat organic wastewater.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63325983A JPH02172597A (en) | 1988-12-26 | 1988-12-26 | Treatment of organic sewage |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63325983A JPH02172597A (en) | 1988-12-26 | 1988-12-26 | Treatment of organic sewage |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02172597A JPH02172597A (en) | 1990-07-04 |
| JPH0310399B2 true JPH0310399B2 (en) | 1991-02-13 |
Family
ID=18182780
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63325983A Granted JPH02172597A (en) | 1988-12-26 | 1988-12-26 | Treatment of organic sewage |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02172597A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0751239B2 (en) * | 1990-07-13 | 1995-06-05 | 荏原インフイルコ株式会社 | How to purify water |
| CA2095804A1 (en) * | 1992-06-19 | 1993-12-20 | John K. Berrigan, Jr. | Combined metals and carbonaceous components removal in a biophysical treatment system |
| JP3582152B2 (en) * | 1995-06-20 | 2004-10-27 | 東陶機器株式会社 | Wastewater treatment apparatus and its operation method |
| AU2001233141A1 (en) | 2000-02-04 | 2001-08-14 | America Online Incorporated | Methods and systems of automated client-server data validation |
| DE60316195T2 (en) * | 2003-02-26 | 2008-05-29 | Degremont S.A. | METHOD AND DEVICE FOR TREATING WATERS CONTAINING, IN PARTICULAR, SUSPENDED CONTAMINANTS |
-
1988
- 1988-12-26 JP JP63325983A patent/JPH02172597A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02172597A (en) | 1990-07-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3368938B2 (en) | Wastewater treatment method and apparatus | |
| JPH0310399B2 (en) | ||
| JP2992692B2 (en) | Sewage purification method and apparatus | |
| JPH0647118B2 (en) | Organic wastewater treatment method | |
| JPH0366036B2 (en) | ||
| JP4608069B2 (en) | Wastewater treatment equipment | |
| JP3377346B2 (en) | Organic wastewater treatment method and apparatus | |
| JPH0639396A (en) | Method for treating waste water | |
| JPH0649197B2 (en) | Organic wastewater treatment method | |
| JPH0352699A (en) | Treatment of sewage of night soil system | |
| JPH0230320B2 (en) | ||
| JPH0310398B2 (en) | ||
| JPH091187A (en) | Waste water treating device and its operating method | |
| JPH0567359B2 (en) | ||
| JPH0471699A (en) | Method for purifying water | |
| JP2779128B2 (en) | Method and apparatus for treating sewage sludge and its separated liquid | |
| JPH0141118B2 (en) | ||
| JP2002018488A (en) | Method and apparatus for treating wastewater | |
| JPH0511520B2 (en) | ||
| JPH1028995A (en) | Treatment of waste water | |
| JPH0217238B2 (en) | ||
| JPH0632834B2 (en) | Organic wastewater treatment method | |
| JPH02222796A (en) | Treatment of organic sewage | |
| JP4467748B2 (en) | Waste water treatment equipment | |
| JPH0535038B2 (en) |